题干

母亲节前夕,阳阳对妈妈给外婆购买的“XX牌”苏打饼干及其配料表产生了浓厚的兴趣.在化学课上,阳阳听老师说过,苏打是碳酸钠(Na2CO3)的一个俗名,她再仔细阅读该饼干的配料表如下:小麦粉、小苏打….她思考:配料中小苏打有何作用?如何鉴别苏打(Na2CO3)和小苏打(NaHCO3)?…

下面是阳阳进行的研究性学习过程,请你参与并回答相关问题.

【资料获悉】

相同条件下,Na2CO3溶液比NaHCO3溶液的碱性强;

20℃时,Na2CO3、NaHCO3的溶解度分别为21.3g和9.6g;

NaHCO3在2700C时能发生如下分解反应:2NaHCO3 __ Na2CO3+H2O+CO2↑而Na2CO3受热不易分解.

上一题 下一题 0.0难度 选择题 更新时间:2012-02-24 03:48:32

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